after reading the doX at www.lovedata.com 
{ here u'll find a copy of that document }
wanted to try to code an little eXample with the use of ibApi
like some AttachTo a db and then to play with transactions at the API level
i took the funtions from that site and after tweeking a little bit i have done 
the following


function AttachDatabase(DatabaseName, userName, password: string): isc_db_handle;
var Buffer: array[0..1023] of char;
  BufPtr: integer;
  dbName: array[0..255] of char;
  status: status_vector;
  IBerrCode: isc_status;
  dbHandle: isc_db_handle;
begin
  StrPCopy(dbName, DatabaseName);
  dbHandle := nil;
    {init the Database Param buffer}
  FillChar(Buffer, sizeof(Buffer), #0);
  BufPtr := 0;
  Buffer[0] := char(isc_dpb_version1);
  inc(BufPtr);
  Buffer[BufPtr] := char(isc_dpb_user_name);
  inc(BufPtr);
  Buffer[BufPtr] := char(length(username));
  inc(BufPtr);
  StrPCopy(@Buffer[BufPtr], username);
  inc(BufPtr, length(username));
  Buffer[BufPtr] := char(isc_dpb_password);
  inc(BufPtr);
  Buffer[BufPtr] := char(length(password));
  inc(BufPtr);
  StrPCopy(@Buffer[BufPtr], password);
    inc(BufPtr, length(password));
    {Attach Database Call }
  try
  IBerrCode := isc_attach_database(@status, 0, @DBName, @DBHandle, BufPtr, @Buffer);
  except
  if IBerrCode <> 0 then HandleIBErrors(@status);
  end;
  Result := dbHandle;
end;




once i made the function i needed to try it 
look out mam i can Attach:



procedure TForm1.bAttachDbClick(Sender: TObject);
  begin
  LoadApi();
  dbhandle:=AttachDatabase('C:\Program Files\InterBase Corp\InterBase\examples\database\employee.gdb','sysdba','masterkey');
  end;




first the gds32.dll must be loadeed somewhere in mem
this is done in loadApi func
in the ibProcs.pas unit
after that lets see what version we have there 




procedure TForm1.Button1Click(Sender: TObject);
begin
  memo1.clear;
  Memo1.lines.add('Version:'+GetVersion);
  memo1.Lines.add('Site:'+getDBSitename)
end;



here we get the info stuff (i took this from freeIB)


 function GetVersion: String;
 var
  local_buffer: array[0..1024 - 1] of Char;
  DBInfoCommand: Char;
  status: status_vector;
 begin
  DBInfoCommand := Char(isc_info_version);
  isc_database_info(@Status, @dbHandle, 1, @DBInfoCommand,
                                          1024 , local_buffer);
  local_buffer[5 + ord(local_buffer[4])] := #0;
  result := String(PChar(@local_buffer[5]));

end;

function GetDBSiteName: String;

var
  local_buffer: array[0..1024 - 1] of Char;
  p: PChar;
  DBInfoCommand: Char;
  status: status_vector;
begin
  DBInfoCommand := Char(isc_info_db_id);
  isc_database_info(@Status, @dbHandle, 1, @DBInfoCommand,
                        1024, local_buffer);
  p := @local_buffer[5 + ord(local_buffer[4])]; // DBSiteName Length
  p := p + ord(p^) + 1;                         // End of DBSiteName
  p^ := #0;                                     // Null it.
  result := String(PChar(@local_buffer[6 + ord(local_buffer[4])]));
end;



after playing with ataching we must see how the transactions should worK


procedure TForm1.bStartTransactionClick(Sender: TObject);
var errcode:integer;
status: status_vector;
 begin
  teb.db_ptr:=@DBHandle;
  teb.tpb_len:=0;
  teb.tpb_ptr:=nil;
  Transaction:=StartTransaction(teb);
end;

function StartTransaction (const tebarray:array of isc_teb):isc_tr_handle;
 var
   status:status_vector;
   IBerrCode:isc_status;

 begin
   result:=0;
   IBerrCode:=isc_start_multiple(@status,@result,1,@tebarray);
   //IBerrCode:=isc_start_transaction(@status,@result,1,@dbhandle,1,@tebarray);

   if IBerrcode <> 0 then HandleIBErrors(@status);
 end;




Compiled version with source is near here ib_api_eXample.zip